The present invention relates to a battery monitoring system and, more particularly, to a battery monitoring system that can centrally monitor, at a host, the state of secondary batteries (hereinafter referred to as batteries) mounted in terminals such as terminals operating in a client/server environment or terminals having an online connection capability.
Traditionally, rechargeable batteries are used as power supplies in notebook computers and other portable information terminals such as handheld terminals and palmtop terminals. These electronic apparatuses are operated by the power supplied from such batteries.
However, the power that can be supplied through discharge of a battery is generally limited by the amount to which the battery is charged, and when the battery becomes low, it must be recharged. Further, the battery lifetime, as a power supply, is limited as the battery characteristics degrade through repeated discharging and charging. Finally, the battery itself has to be replaced by a new one.
Here, as the battery is usually mounted inside an apparatus, and since it is not possible to see the internal condition of the battery, it is difficult to know the state of the battery, such as the remaining capacity in the battery, from outside the battery. This may result in a situation where, during the use of the apparatus, the battery is exhausted, rendering the apparatus inoperable. Furthermore, as is often the case, the battery is replaced only after it is noticed that the battery is no longer rechargeable.
To avoid such situations, various strategies have been proposed that detect the operating state of the battery mounted in an apparatus and alert the user of the apparatus to the detected state.
For example, it is practiced to detect the output voltage of the battery mounted in the apparatus and, based on the result of the detection, visually indicate the remaining capacity of the battery on the display unit of the apparatus or produce an indication or notification alerting the user that the battery is low and needs recharging. In response to such an indication or notification, the user of the apparatus recharges the battery.
In the case of electronic apparatus such as terminals operating in a client/server environment where a plurality of terminals can connect to a server, it is also practiced for the server to centrally monitor the output voltage of the battery mounted in each terminal.
In some implementations, the remaining capacity of the battery in each terminal is centrally monitored at the server which, based on the remaining capacity, determines whether the terminal has enough battery capacity to be able to continue operation; if the remaining battery capacity is too low to continue operation, the battery of that terminal is recharged. This is to prevent a situation where the battery of the terminal is exhausted during data transfer between the client and the server, causing an interruption in the data transfer and resulting in an apparatus operation error.
Traditionally, monitoring of the battery mounted in an electronic apparatus has been performed mainly to have the battery recharged or to extend the battery life. Accordingly, in the prior art, it has been practiced to replace the battery by predicting battery replacement time from elapsed time based on the battery life predefined in terms of operating hours and the number of recharges, or after an operational trouble attributable to the battery has occurred.
In the prior art, it has not been possible to accurately determine the battery replacement time based on the battery life, because the life of the battery mounted in an electronic apparatus varies depending on its conditions of use, frequency of use, and further on the battery characteristics that differ for each individual battery. In particular, when a plurality of terminals are installed in a retail store or an office, it is standard practice to perform replacement and maintenance work on the batteries mounted in the respective terminals collectively on a store-by-store or office-by-office basis; as a result, in such cases where, of the plurality of terminals, some terminals have been used more frequently than the others, it has been practiced, from the viewpoint of maintenance efficiency, to replace the batteries that have not yet reached the end of life, together with the batteries that are no longer serviceable and should therefore be replaced, thus resulting in wasteful replacement.
The prior art, therefore, has had the problem that the change in the battery life cannot be monitored in real time and accurately because the purpose is limited to the method of charging the battery mounted in an electronic apparatus or to the extension of the battery life.
It is accordingly an object of the present invention to provide a battery monitoring system wherein, for the batteries mounted in terminals, the operating state of each battery is centrally monitored at the host, thereby preventing the occurrence of trouble and achieving efficient, effective, and appropriate battery replacement and maintenance work.
To solve the above problem, according to the present invention, a battery monitoring system for monitoring the batteries mounted in a plurality of electronic apparatuses and used to operate the electronic apparatuses comprises: battery monitoring means for gathering battery state information concerning the battery mounted in each electronic apparatus; battery monitoring and controlling means for determining, based on the battery state information, whether the battery has reached an end-of-life time; and output means for outputting the battery state information including the end-of-life time.
The battery state information includes total operating time during which the electronic apparatus has been operated by the same battery mounted therein, wherein the total operating time is obtained by detecting a power off state of the electronic apparatus and by sequentially adding up the operating time during which the electronic apparatus has been operated by the battery.
Further, the battery state information includes the number of recharges that have been performed on the same battery mounted in the electronic apparatus, or includes actual operating time during which the electronic apparatus has been operated by the same battery on a single charge after completion of charging, wherein the actual operating time is obtained by measuring the time elapsed from completion of a recharge until a battery output voltage being monitored by the battery monitoring means drops to a predetermined voltage.
The battery monitoring and controlling means, when determining whether the end-of-life time of the battery has been reached, can refer to a consumption level index that has been set according to the conditions of use of the battery; the battery monitoring and controlling means can also acquire the battery state information including an error event associated with the same battery mounted in the electronic apparatus and the number of occurrences thereof, and can determine, based on the information, whether the end-of-life time of the battery has been reached.
The electronic apparatus is an information terminal, and the output means transmits the battery state information, including the end-of-life time, at periodic intervals to a server connected to the information terminal, wherein the server is installed in a retail store or the like, manages a plurality of information terminals, and transfers the battery state information to a host connected to the server, and the host indicates, for each store or the like, any information terminal that is to be subjected to battery maintenance scheduled next time.